From owner-freebsd-current@FreeBSD.ORG Sat Apr 14 09:07:39 2012 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 47F0E106564A; Sat, 14 Apr 2012 09:07:39 +0000 (UTC) (envelope-from jeremie@le-hen.org) Received: from smtp5-g21.free.fr (smtp5-g21.free.fr [IPv6:2a01:e0c:1:1599::14]) by mx1.freebsd.org (Postfix) with ESMTP id 056E38FC0C; Sat, 14 Apr 2012 09:07:36 +0000 (UTC) Received: from endor.tataz.chchile.org (unknown [82.233.239.98]) by smtp5-g21.free.fr (Postfix) with ESMTP id 06180D4804B; Sat, 14 Apr 2012 11:07:29 +0200 (CEST) Received: from felucia.tataz.chchile.org (felucia.tataz.chchile.org [192.168.1.9]) by endor.tataz.chchile.org (Postfix) with ESMTP id 9EC2B923; Sat, 14 Apr 2012 11:07:28 +0200 (CEST) Received: by felucia.tataz.chchile.org (Postfix, from userid 1000) id 7858261F7; Sat, 14 Apr 2012 09:07:28 +0000 (UTC) Date: Sat, 14 Apr 2012 11:07:28 +0200 From: Jeremie Le Hen To: Alexander Best Message-ID: <20120414090728.GA8798@felucia.tataz.chchile.org> Mail-Followup-To: Alexander Best , freebsd-current@freebsd.org References: <20120413213644.GA92873@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120413213644.GA92873@freebsd.org> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-current@freebsd.org Subject: Re: howto debug a complete hard reset X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 14 Apr 2012 09:07:39 -0000 Hi Alexander, On Fri, Apr 13, 2012 at 09:36:44PM +0000, Alexander Best wrote: > > i'm running HEAD on amd64 and experienced some really annoying resets during > the last couple of months. > > when i do 'sysctl -a' or 'sysctl -a|grep bla', my whole system does a hard > reset. no core dump gets produced. > > isn't there a way to find out which sysctl variable is causing the reset? This is probably a sysctl handler that is causing the reboot. You can run this one-liner to spot the culprit (use sh): for i in $(sysctl -Na); do sysctl $i >> ~/sysctl.out; sync; done Each sysctl will be called in turn and the output is appended to a file, but the file will forcibly written to the disk before the next occurence. When your computer will be reset, the culprit will obviously not be written to this file, but the previous one will. You can then look at the output of sysctl -Na to see which one is causing the reboot. Regards, -- Jeremie Le Hen Men are born free and equal. Later on, they're on their own. Jean Yanne